Attitude indicator for divers

Abstract

A device for enabling a diver to determine his relationship to the true horizon in deep and murky waters or when physiological sensations are of little value is described. An attitude sensor, incorporating a series of mercury switches, usually at the back of the diver's helmet or head, is coupled to a series of light emitting diodes equally spaced around the periphery of the face plate of the diving mask or helmet so as to simulate the natural observation that the half space above the horizon is illuminated while the half space below the horizon is not.

I claim: 
     
       1. An attitude indicator for attachment to a movable body and operable connection to a power supply means, said indicator comprising: (a) a visual display means;   (b) attitude sensor means including a switch body having a conical cavity therein; a conducting liquid partially filling said cavity; a conically shaped common electrode means relatively smaller than said cavity axially located within said cavity and a plurality of electrical contacts at different locations in said cavity, each electrically interconnected electrically to a power supply and a selected part of said visual display means when said conducting liquid is in contact therewith.   
     
     
       2. An attitude indicator as claimed in claim 1 wherein said movable body is a diver and said visual display means is incorporated head gear adapted to be worn by said diver. 
     
     
       3. An attitude indicator as claimed in claim 2, wherein said visual display means comprises a plurality of light emitting diodes each connected to a selected one of said electrical contacts. 
     
     
       4. An attitude indicator as claimed in claim 1 wherein said sensor means has means to secure it to the head of a diver. 
     
     
       5. An attitude indicator as claimed in claim 1, wherein said visual display means comprises a plurality of light emitting diodes arranged around the periphery of a diver's face plate and each electrically interconnected to a selected one of said electrical contacts such that, when said diver is in a vertical plane relative to a horizon, half of said light emitting diodes are illuminated and indicative of a half space above said horizon, and when said diver is in a horizontal plane relative to said horizon all said light emitting diodes are illuminated or extinguished indicative of a face-up or face-down attitude respectively. 
     
     
       6. An attitude indicator as claimed in claim 1 wherein said conducting liquid is mercury. 
     
     
       7. An attitude indicator as claimed in claim 6 wherein said common electrode means is in permanent contact with said mercury. 
     
     
       8. An attitude indicator as claimed in claim 1, wherein said cavity is a right conical cavity and said common electrode means is a right cone. 
     
     
       9. An attitude indicator as claimed in claim 1, wherein said conical cavity is a right conical cavity, said conically shaped common electrode means is a right cone, and wherein said plurality of electrical contacts are equally radially spaced around said cavity in a single plane adjacent the base thereof.